This grant has supported work dealing exclusively with the disign and development of new histochemical methods for enzymes and functional groups of macromolecules for both the light and electron microscope. With the recent development of a very specific method for prostatic acid phosphatase (PAP) we will continue to study the pattern of distribution of PAP in normal prostatic epithelium and prostatic adenocarcinoma both with the light and electron microscope. We have also discovered PAP in epididymis and spleen of some species. We will try to illucidate the differences in these PAP sources if we can. The program dealing with drug design and drug development for prostatic carcinoma is supported since March 1974 by a research grant from the National Prostatic Cancer Project, N.C.I. However, tissues from treated primates will be studied by this electron microscopy team. BIBLIOGRAPHIC REFERENCES: Design of Spindle Poisons Activated Specifically by Prostatic Acid Phosphatase (PAP) and New Methods for PAP cytochemistry. A.M. Seligman, N.J. Sternberger, B.D. Paul, A.E. Friedman, W.A. Shannon, Jr., H.L.- Wasserkrug, R.E. Plapinger and D. Lynm. Cancer Chemotherapy Reports, Part 1, 59:233, 1975. The Ultrastructural Localization of Cytochrome Oxidase via Cytochrome, Winston A. Anderson, Gonul Bara and Arnold M. Seligman, J. Histochem. Cytochem. 23:13, 1975.